Electric drive for the picking devices for looms



" E F. PHILY 1 2,067,096

ELECTRIC DRIVE THE PICKING DEVICES FOR LOOMS Filed July 15, 1933 Elli UNITED STATES PATENT OFFICE ELECTRIC DRIVE FOR. THE PICKING DEVICES FOR LOOMS Fernand Phily, Lyon, France Application July 13, 1933, Serial No. 680,320 In Germany July 14, 1932 7 Claims. (Cl. 139142) In order to obtain the most uniform force of stroke possible, which is also independent of the sett. for looms in which the sett can be regulated by altering the speed of rotation of the crankshaft, a proposal has already been made to provide a special electromotor for driving the picking shaft, it being possible to regulate the speed of the said electromotor independently of the main motor driving the crankshaft. In accordance with the proposal, the picking shaft turns continuously and is coupled to the picking eccentrics, which are fitted to the said shaft in such a way as to be able to rotate, by means of controllable couplings, at the beginning of each shot. The disengageable couplings are controlled by an intermediate shaft fitted with cams and driven by the loom crankshaft at a suitable speed. The said intermediate shaft can also be fitted co-axial to the picking shaft.

In this form of drive, the desired independence of the stroke force from the sett is obtained, but this advantage is purchased at the cost of such disadvantages that the proposed form ofdrive has not yet been generally adopted in practice. 0n the one hand, the controllable couplings represent a source of trouble, which must not be under-estimated, and which, under certain circumstances, can lead to a serious reduction of the output, and, on the other hand, they result, with the intermediate shaft necessary for driving them, in an undesirable complication in the design of the whole loom and the drive.

The present invention is based on the knowledge that the construction of the loom can be simplified and that the stroke force can be made independent of the sett, if the picking sticks of the loom are driven directly by suitable electrical apparatus. According to the present invention, each picking stick is driven by an electric motor, which is automatically switched on, as actuated by the rotation of the crankshaft, at the beginning of the stroke, and switched off again when the stroke is finished. The idea of the invention can be realized most simply by attaching the picking stick directly to the shaft of the motor. In this case, the motor performs only a fraction of a revolution for each stroke and can also be replaced by a turning solenoid. In accordance with the present invention, the stroke force can be altered in the desired manner by changing the torque of the motor by means already generally known, e. g. by inserting resistances before the field windings or in the armature circuit of the motor. It is advantageous to limit the rotation of the motor or the motion of the picking sticks by means of stops, which can be of an elastic nature. Furthermore, it is advantageous to bring the picking stick back automatically into its original position when the stroke is finished. This can be effected by means of springs or 5 weights, or by reversing the direction of rotation of the motor for a short space of time.

It is advisable to use switches with electric remote control for switching the picking stick motors on and off. The control circuits of the said switches should be arranged in such a way as to be dependent on the rotation of the crankshaft or on the motion of a device for the formation of the shed or for beating up. A very advantageous form of control device for the picking stick motors is obtained by providing two switches, one of which is actuated at every rotation of the crankshaft at the moment at which the shot has to take place, and the other of which is a change-over switch, actuated at every revolution of. the crankshaft, for the motor switch control circuits.

The illustration shows an example of the invention. l and 2 are the picking stick motors, fed from the mains 5 through the switches 3 and 4 with remote control windings 3a and 4a.. 6 is a cam disc fixed to the Crankshaft of the loom. The said cam disc 6 actuates the change-over switch it by meansof the pawl 9 and the ratchet-wheel In which is mounted on the same shaft as switch H, and also actuates button switch 8 by means of the'cam I. I2, I3, and I 4 are the contact fingers of the change-over switch II, which-is shown as a drum switch.

As above stated, the picking sticks 24 and 25 are advantageously attached directly to the shafts 22 and 23 of the respective motors I and 2. The rotation of the motor or the motion of the picking sticks is limited by stops Ila, l'lb, l8a, I8b, which can be of an elastic nature. 40 In the particular example shown in the figure, these stops are shown 180 apart, but the stops could just as well be arranged 270 apart or other desired arc, as required, since my arrangement is equally applicable to any desired angular separation. The figure shows a way of applying my arrangement to a conventional loom structure having a shuttle l9 and shuttle brakes 20, 2|. The crank shaft of the loom is shown at l6 carrying the cam disc 6.

The motor torque is changed as desired by inserting resistances in the field windings or in the armature circuit of the motors. An example of such resistance control is shown schematically by the variable resistances I 5a and I 5b shown inserted in series in the leads 5c and 5d of motors I and 2. It will be understood that if desirable, similar variable resistances can be inserted in motor leads 5a, 51), 5e, 5f, or in the motor field windings, these other conventional motor control arrangements not being shown in the drawing. Springs 25 and 26 are provided to bring the picking stick back into its original position when the stroke is finished, and are belt-connected to motor shafts 22 and 23.

The working of the above described device is as follows: When the cam disc 6, connected to the crankshaft of the loom, turns in the direction of the arrow, the changeover switch I I is moved one notch forward by means of the pawl 9 and the ratchet-wheel I0. If, for instance, the contact fingers I2 and I3 were connected before the commencement of this operation, the fingers I3 and I4 are now connected, thus preparing the circuit for the remote-control switch 3. When the crankshaft turns further, the cam 1 of the disc 6 engages with the button-switch 8 at the moment at which the shot has to take place. The said switch 8 closes the control circuit of the switch 3 and thus switches in the picking stick motor I. When the stroke is finished, the cam 1 releases the button-switch 8 and the picking stick motor I is switched off. When the crankshaft turns still further, the change-over switch I I is again moved forward and, through the connection of the contact fingers I2 and I3, the circuit is prepared for switching in the picking stick motor 2 by means of the switch 4. When the cam 'I then engages with the button-switch B, the picking stick motor 2 is switched in. At the next rotation of the crankshaft, motor I is connected to the mains, at the following rotation, motor 2, and so on.

The application of the present invention is not limited to looms, but can also be used for similar machines, necessitating a motion resembling the shot in a loom.

Having now particulary described and ascertained the nature of my invention and how the same is to be performed, what I claim is:

1. An electric drive for the picking device of a loom comprising an electric motor having a rotor, a picking stick attached to the rotor of said motor for rotation therewith, said loom having a driving shaft, and means controlled by said shaft for automatically switching on the motor at the beginning of the picking motion and again automatically switching off the motor at the end of the picking motion.

2. An electric drive for the picking device of a loom comprising an electric motor having a rotor, a picking stick attached to the rotor of said motor for rotation therewith, said loom having ,a driving shaft, and means controlled by said shaft for automatically switching on the motor at the beginning of the picking motion and again automatically switching off the motor at the end of the picking motion, and means for returning the picking stick to its starting position.

3. An electric drive for the picking device of a loom comprising an electric motor having a rotor, a picking stick attached to the rotor of said motor for rotation therewith, said loom having a driving shaft, and means controlled by said shaft for automatically switching on the motor at the beginning of the picking motion and again automatically switching off the motor at the end of the picking motion, and stops mounted adja-' cent said picking stick for limiting its rotary motion.

4. The structure of claim 1, and means for returning the picking stick to its starting position, and stops adjacent said picking stick for limiting its rotary motion.

5. The structure of claim 1, and resilient stops cooperating with said picking stick for limiting its path of movement.

6. An electric drive for the picking device of a. loom comprising a plurality of motors each having a rotor, a picking stick attached to each rotor for rotation therewith, an electric circuit for said motors and a driving shaft for said loom, a switch and a change-over switch in said circuit operated from said shaft, means for actuating said first switch to close the circuit to operate one of said motors, and means for actuating said change-over switch to switch in the second motor in the circuit after the completion of operation of said first motor.

7. An electric drive for the picking device of a loom comprising a plurality of motors each having a rotor, a picking stick attached to each rotor for rotation therewith, an electric circuit for said motors and a driving shaft for said loom, a switch and a change-over switch in said circuit, a cam on said shaft, said cam operable to actuate said first switch, a ratchet wheel for driving said change-over switch, a pawl cooperating with said ratchet wheel, said pawl actuated by said cam.

FERNAND PHILY. 

